AG. 225 AGRICULTURAL SYSTEMS/ELECTRICITY AND HYDRAULICS

Transcription

1 AG. 225 AGRICULTURAL SYSTEMS/ELECTRICITY AND HYDRAULICS COURSE DESCRIPTION: A course designed to develop skills in operation of tools and equipment, wiring, controls, electric motors, and hydraulics. UNITS OF INSTRUCTION MINUTES OF INSTRUCTION Safety 235 Electric Tools and Equipment 235 Electricity and Wiring 1,175 Electrical Controls 940 Electric Motors 940 Agricultural Hydraulic Systems 705 A. Safety TOTAL MINUTES 4, Identify safety equipment necessary for agricultural power technology 2. Apply basic laboratory safety instruction 3. Describe safety practices when using electrical equipment 4. Apply safety practices when using tools and equipment B. Electrical Tools and Equipment 1. Identify, adjust, maintain and properly use the following tools: a. volt meter b. amp meter c. ohm meter d. portable GFCI e. wire stripper f. circuit tester g. continuity tester h. linesman pliers i. conduit bender j. fish-tape k. deburring tool l. growler

2 C. Electricity and Wiring 1. Describe electrical energy and how it works 2. Define common electrical terms and their relationships 3. Determine the amount of electrical energy used 4. Compute the cost of using electrical energy 5. Read and interpret wiring plans 6. Locate and mark routes for small appliances, general purpose and individual circuits 7. Install device boxes and outlet boxes 8. Install 120-volt, 120/240-volt circuits 9. Connect receptacles, switches and fixtures for each circuit 10. Ground the electrical system and equipment 11. Determine the type and size of service entrance equipment to install 12. Install service entrance equipment using cable or conduit with overhead or underground conductors 13. Install ground fault circuit interrupters 14. Install conduit 15. Estimate wiring costs 16. Install wiring for agricultural and other utility buildings D. Electrical Controls 1. Describe the function and importance of controls and control circuits in the operation of electric equipment 2. Explain the terminology and symbols used in discussing electric control circuits 3. Identify the characteristics of automatic and non-automatic control systems 4. Identify the characteristics of switches most commonly used in control circuits 5. Connect the tumbler switch having a built-in overload protector into a motor circuit 6. Explain how the overload protection device protects the motor from shore circuit or overload damage 7. Identify the function of a limit switch 8. Connect a limit switch into a motor circuit 9. List the characteristics of relays and the function of relay devices in control circuits 10. Connect the relay into a control circuit 11. Connect a time-delay relay into a motor control circuit 12. Identify the characteristics and types of motor control devices in an electrical circuit 13. Connect a commercial type starter switch and stop-start push-button stations into a motor control circuit 14. Describe the automatic sensing control devices available and how they might be applied in the control circuits used on the farm and in the home 15. Connect automatic sensing control devices into a control circuit 16. Explain how the automatic sensing control devices control an electric load

3 E. Electric Motors 1. Describe factors needing consideration if electric motors were to be replaced by alternative power sources 2. Use nameplate information to describe an electric motor 3. Identify electric motors by type 4. Match types of electric motors to starting load and duty characteristics 5. Identify major construction characteristics of electric motors by type of enclosures, mounts, bearings and lubrication systems 6. Spot motor ailments by sight, sound and touch 7. Use an organized trouble shooting procedure to identify the specific problem 8. Decide which problems can be corrected in place and which require removal to repair station 9. Identify possible causes and results of overloading an electric motor without overload protection 10. Recognize the modus operandi for overload protection devices 11. Replace or reset activated overload protection devices 12. Determine and order proper size of components for drive systems needing replacement 13. Remove and replace the needed drive systems 14. Explain how the poles of permanent magnet and electro-magnet attract and repel each other 15. Describe how the attracting and repelling forces of an electro-magnet can cause a free rotating magnet to turn 16. Identify a split-phase motor and a shaded-pole motor based on major internal parts and characteristics 17. Explain the operating principles of a split phase and shaded-pole motor integrating the parts and characteristics identified 18. List and describe loads requiring low starting torque 19. Identify capacitor-start motors based on major internal parts and characteristics 20. Explain the operating principles of the capacitor start motor integrating the parts and characteristics identified 21. List and describe loads requiring moderate starting torque 22. Identify repulsion-start and universal motors based on major internal parts and characteristics 23. Explain the operating principals of a repulsion start and universal motors integrating the parts and characteristics identified 24. List and describe loads requiring high starting torque 25. Identify electric motors that are reversible and are dual-voltage based on operating principles, nameplate information and wiring diagrams 26. Identify the leads to the starting and running windings of electric motors 27. Explain the operating principles involves when changing rotation and/or voltage of electric motors

4 28. Change the rotation and voltage of electric motors 29. Use the following terms in analyzing electric motors: a. torque b. starting current c. horsepower d. voltage drop e. efficiency f. power factor g. apparent power h. real power 30. Use a prony break, watt meter, volt meter, amp meter and appropriate formulas to collect data on various motors 31. Analyze the data and draw appropriate conclusion 32 Select an electric motor for a particular work situation according to the following variables: a. power requirement of the load b. capacity of the electric service entrance c. speed requirements of the load d. duty time required e. starting torque required f. direction of rotation g. cost 33. Select the type of motor enclosure needed for a particular environment 34. Select the type of bearings and lubrications system needed based on the method and frequency of lubrication and the mounting position 35. Use a manufacturer's catalog and order the motor most nearly matching specifications given 36. Select the correct size of wire for the electric motor used 37. Order or purchase materials for installation of a motor 38. Evaluate hypothetical or real motor installations F. Agricultural Hydraulic Systems 1. Identify the applications of hydraulics in agriculture 2. Identify the components of a hydraulics system 3. Define terminology associated with hydraulic systems 4. Describe operating principles of hydraulic systems 5. List the advantages and disadvantages of utilizing hydraulics in agriculture 6. Read and interpret basic hydraulic schematic diagrams 7. Select the proper hydraulic fluid for a specific hydraulic system and operating condition 8. Drain, flush and refill hydraulic systems on agricultural equipment 9. Service and maintain hydraulic seals and packings 10. Select hydraulic tubing, pipe and remove hoses to fulfill specific pressure, volume and exposure requirements 11. Service, maintain and/or operate hydraulic fittings and couplers

5 12. Service and maintain hydraulic fluid filters 13. Trouble-shoot hydraulic motor operating problems 14. Select hydraulic motors to fit specific applications on agriculture equipment and power units 15. Determine relief valve pressure setting by the T-test method